FABRIC: Sprints OG hats are made with a proprietary blend of featherweight fabric. The 100% polyester is buttery soft and durable. FIT & SIZE: Each hat is made with a premium Velcro closure allowing the hat to adjust and fit most adult head sizes. The circumference is 22.8 inches and expands to about 24.3 inches which is a hat size 6 & 1/4 to 7 & 7/8. FIGHTS SWEAT: A built in sweat band wicks sweat away from your face and eyes while teardrop mesh vents allow heat to escape keeping you cool on your workout. HAND WASH ONLY: Wash your Sprints hat in cold water, alone with the Velcro completely closed and hang to dry.